1. Field of the Invention
The present invention relates to a filter core and manufacturing method thereof and, in particular, to a filter core for filtering suspended particles from fluid.
2. Description of the Prior Arts
A conventional filter core of a filtering device, such as U.S. patent application Ser. No. 14/063,497, comprises a wavy filtering layer and a flat filtering layer rolled into the shape of a cylinder and alternately stacked. Axial sealing adhesive layers are respectively coated along peaks of the wavy filtering layer to be adhered to the flat filtering sheet to enhance the connecting strength between the wavy filtering sheet and the flat filtering sheet. However, this conventional filtering core has the following shortcomings.
Multiple channels are formed between the wavy filtering sheet and the flat filtering sheet. End sealing adhesive layers are respectively adhered in ends in one of the axial sides of half of the channels and ends in another axial side of the other half of the channels. Thus, the fluid to be filtered, such as air, enters half of the channels from one axial side, moves to the other end of said channels, and hits the end sealing adhesive layer. Then, the fluid directly passes through the wavy filtering sheet or the flat filtering sheet to arrive at the other half of the channels, such that the fluid can flow out of the filter core. When the fluid passes through the wavy filtering sheet or the flat filtering sheet, the filtering sheet filters the fluid. However, the filter core filters the fluid only when the fluid passes through the filtering sheet. Thus, the filtering effect of the conventional filter core is insufficient.
Besides, during the forming process of some of the filter cores, when the wavy filtering sheet and the flat filtering sheet are adhered but are not rolled yet, the adhered filtering sheets are silt-cut. The adhered filtering sheets are cut along one of the end sealing adhesive layers to align with an outer surface of the end sealing adhesive layer and a side of the adhered filtering sheets, thereby effectively making use of an axial length of the filter core to maximize the filter core. However, the conventional slit-cutting method has the following shortcomings.
The conventional slit-cutting is done by a press cut, which is using a pressing blade to directly press downward to achieve the cutting. However, the movement of the press cut may flatten and deform the cut edge of the adhered filtering sheets, which makes the edge of the adhered filtering sheets and the edge of the rolled filter core uneven.
To overcome the shortcomings, the present invention provides a filter core and manufacturing method thereof to mitigate or obviate the aforementioned problems.